On 1 January, Yassin al-Haj Saleh posted these words on his Facebook page. Al-Haj Saleh spent 16 years in Assad’s prisons after being arrested as a student in the 1980s for being a member of a communist group. He is now a prominent dissident known for his sharp analysis of the Syrian conflict. I check his page every day.

The words were accompanied by a video. Clearly, one of the great many videos circulating showing the cruelty of the regime’s militias, the widely feared shabiha. I hesitated before opening it. These videos are evidence. But it’s always the same question: how badly will I regret seeing it?

Shabiha wearing military uniforms hold several young men hostage, somewhere on a staircase. The hostages face the wall, blindfolded, their hands cuffed behind them, their bent shoulders facing the camera. The uniformed men rip their shirts off and thrust long, thin knives into their backs and necks: as if they were slaughtering sheep. Slowly and artfully they stab, chopping flesh out until the men lie on the ground, bleeding, their screams muffled by the cloth around their faces. The shabiha pick up concrete blocks and smash them on the bodies on the ground, breaking their bones and skulls. White dust fills the frame. The shabiha shake it off their hands. It looks almost as though they are clapping, congratulating themselves. Not the slightest sign of discomfort: they are chatting and laughing. Their intent wasn’t only to kill: carrying guns, they could have shot their adversaries. They wanted to inflict pain, to demonstrate power, to show that the enemy is subhuman. Five minutes so unbearable that one commenter on the post writes: ‘That’s the first time in my life watching something has made me dizzy. I’m still trying to catch my breath, to remember I’m human.’

Al-Haj Saleh’s posts are usually followed by hundreds of comments, including many from key Syrian activists and long-time members of the opposition. This time a heated controversy breaks out. One commenter writes: ‘What new information does this video add? What do we not already know about the sadism of the shabiha? Who can maintain his humanity while seeing this video?’ He fears that images such as these are damaging to the revolution, removing any hope of reconciliation. He pleads for them to be kept only for use as evidence in future judicial trials, not released to the public. Others insist that the regime’s brutality should be brought fully to light: nothing should be hidden.

No agreement is reached. But the discussion strikes at the heart of the question that the deeply divided Syrian public doesn’t yet dare face: how to imagine a common future for a country that has seen unimaginable crimes? How much ‘truth’ can a society bear if it wants to heal?

It isn’t an easy question, or a new one. Whether people can forgive and live together again has been a contested issue in the recent history of many countries, from South Africa to Rwanda, the former Yugoslavia, Chile, Cambodia, Lebanon and Iraq. There is no universal solution, and while the blood is still flowing even to ask the question may seem premature. It can probably only find an answer once a minimum of justice has been achieved. But it has to be raised, and the sooner the better. Once Syrians emerge from the present nightmare – in one, three or ten years – they will be forced to look into one another’s eyes. They will have seen and heard things they wish they hadn’t.